Feed water regulator



6, 1931. own v 1,826,058

FEED WATER REGULATOR Filed July 17, 1928 A J2 a ggmmmamu ATTORNEY.

Patented Oct. 6, 1931 UNITED STATES PATENT BENJAMIN F. DOWD, OF LONG BEACH, CALIFORNIA FEED WATER REGULATOR Application filed July 17, 1928. Serial No. 283,465.

.. an automatic control actuated responsive to "5 the thermal differential between the steam and water, .the control device being adapted for reception of steam when the water level is lowered and reception of water when the level rises so that a thermostatic responsive 1O element will be actuated in accordance with control, partly in axial section and separately the difference in temperature to regulate the opening and closing of a valve in the feed water pipe.

i It is an object of the invention to provide a valvular control for the feed water whereby the pressure of either the steam or water in the control device and which is directed against one side of the valve will neutralize the pressure in the feed line between the valve and the boiler, so that the valve will tend to open responsive to the superior pressure, no matter how slight, whichmust be maintained in the feed line leading to the valve, and may 7,

be as readily closed by a force, provided in the present instance by the thermostatic responsive element, which need only be suiiicient to overcome the slight difierential pressure in the feed line at the respective sides of the valve. The invention thus provides an extremely sensitive control which will insure accurate maintenance of a desired water level.

It is a further object of the invention to providefor simple but accurate adjustment of the thermostatic control, with the adjusting means readily accessible for manipulation but being positively packed-0E with relation to the interior of the control device 7 which is adapted to receive either the steam or water and the adjusting means being preferably also so arranged as to reassume any predetermined setting when the device is again operatively assembled after any necessary disengagement of the parts.

It is a still further object of the invention to adapt the control device for a flushing action to clean the same Without disturbing the relative adjustment ofthe parts, and to also provide for access to the valvular control in the feed line by removal of the'control device as a unit and without affecting the assembly of its parts. 7 v

Further objects of the invention will be readily understood from the following de scription of the accompanying drawings, in

which: Fig. 1 is a somewhat diagrammatic showing of a boiler provided with the improved feed watercontrol.

Fig. 2 is a side elevation of the automatic showing the two ends of the structure.

The automatic control is particularly adapted for use in connection with a boiler shown at 1 and having a usual feed water 55 pipe 9.. The boiler may be provided with a usual water column 3 having'a sight gauge 4:, with the water column communicating at its respective ends with the boiler above and below the normal water level as shown at 5 and 6. The automatic control may bemountedin a pipe '7, which is preferably althoughnot necessarily vertically disposed and which communicates at its respectivefends with the feed water'pipe as shown by the couplings 8-9. and a valve 10 in the feed water pipe between these couplings is adapted to be closed for directing the feed water through pipe 7 or may be opened for direct flow of, the feed water without passage through pipe 7 when it is not desired to employ'automatic control.

The automatic control includes a valve casing 20. mounted in pipe and forming a usual I, longitudinally disposed valve seat .Zlioi a valve 22 which is laterally movable in a guide 23, the valve being adapted to open by pressure from the feed water supply so as to permit flow'to the boiler and closing against said pressure for shutting-0E the flow of water to 99 the boiler. Acontrol device for valve 22projects laterally from guide 23, and pipes2425 leading from the respective ends of water column 3 are connected to this control device for supplying steam and water respectively. Valves 11 are preferably mounted in pipe 7 beyond the respective ends of valve casing 20, and are adapted to be opened during operation of the automatic control, but are closed when valve 10 is opened for direct flow of the W feed water without it being subjected to the automatic control, and are also adapted to be closed whenever it is necessary to disconnect the control device from valve casing 20 for cleaning or repairing the automatic control.

The control device projecting from guide 23 preferably includes a sleeve having a tube 31 projecting rearwardly therefrom, with a rod 32 extending through the tube and connected thereto at its rear end by a coupling 33, and the forward end of the rod extending into sleeve 30 and engaging a valve stem 34 which is slidable in the sleeve and engages the valve 22. The pipes 2425 are connected to sleeve 30 in rear of valve stem 34 and preferably in vertical alinement at diametrically opposite ports 35-36, and the entire control device may be removably connected to guide 23 by a coupling collar 37 threaded on guide 23 and engaging sleeve 30 for rotary adjustment of the control device so that the ports 35-36 may be preferably vertically positioned with relation to one another.

The valve stem 34 slides snugly in the bore of sleeve 30 and may be packed-off with relation to the bore by a usual packing gland 40. A pin 41 preferably projects forwardly from the valve stem for reception in a guide 42 on the back of valve 22 so as to simply abut against the valve without axial connection thereto, and the end of the pin is pref" erably slightly rounded as shown at 43 so as to readily permit any play of the valve which may be necessary for it to snugly engage its seat. The stem 34 is preferably of the same diameter as that of the valve seat 21 and boiler pressure directed against the respective ends of the stem neutralizes the fluid pressure on the stem so that the feed water pressure which is directed against the valve and which is superior to the boiler ressure will thus tend to open the valve, iiowever slight this differential pressure may be, and in similar manner the valve may be readily closed against the feed water pressure by sim ly overcoming this differential pressure.

The differential pressure is overcome and the valve closed by abutment of rod 32 against the rear end of stem 34, and for this purpose the rear end of the stem is preferably concave as shown at 45 and the end of rod 32 is rounded as shown at 46 for abutment in the concave recess without axial connection to the valve stem. The rod may thus be retracted without disturbing the valve stem and is also guided concentric with the stem but without radial strain when the rod is protracted for axially shifting the valve stem to close valve 22. The bore of sleeve 30 may form a guide 47 for the operating rod between ports 3536 and the rear end of valve stem 34, but. the bore of this ide is such as to permit the free flow of uid so that the boiler pressure introduced at ports 35-36 will be directed against the valve stem to maintain the balanced valve construction.

The means for retracting and protracting rod 32 to permit opening of valve 22 by the differential pressure and to close the valve against such differential pressure, is shown as a thermostatic responsive element preferably provided by constructing rod 32 and tube 31, which as previously stated are connected at their rear ends by coupling 33, of materials such as suitable metals having appreciably different coeflicients of expansion, so that longitudinal expansion and contraction of the tube, which has a relatively high coefficient of expansion, with relation to the rod having a substantially negligible coefiicient of expansion, will axially shift the rod in sleeve 30 for corresponding axial move ment of stem 34 and valve 22. As an instance of this arrangement the expansible tube 31 may be threaded into the rear end of sleeve 30 in back of ports 353(), and the pposite end of the tube may be threaded 40-52, but is preferably adapted to be drained through a normally closed stop-cock which is connected to a nipple projecting from sleeve 33 and opening into the bore thereof between tube 31 and pat-king The nipple is preferably in axial alineuient with the port 36 which is connected to the pipe 25 leading to the water end of column 3 and which preferably opens downwardly. and fluid will thus readily drain through nipple 54 and the stop-cock 53 when the latter is opened. v

The axially adjustable connection for rod 32 in the bearing 51 is shown as a threaded connection 60, the projecting end of the rod having a head 61 adapted for engagement by a suitable tool for screwing the rod through its bearing, and the rod being preferably locked in adjusted position by a jam nut 62 which is threaded onto the end of the rod for abutment against bearing 51. The jam nut may be preferably fixed in adjusted posi tion along the length of the rod by splitting the nut as shown at 63 and adapting it for clamping engagement on the rod by means of a bolt 64.

The automatic control is connected to the boiler so as to project substantially horizontally at approximately the normal water level in the boiler, and since a corresponding water level will be maintained in the pipes 24-25 the tube 81 will contain either steam or water depending upon the fall or rise or the water level in the boiler, Steam in tube 31 will expand the tube and thereby retract rod 32 to permit opening of valve 22 by the differential pressure against the balanced valve so that water will be supplied to the boiler until the normal level is again reached and the steam in tube 31 is replaced by water. The water will cool and thus contract the tube 31 so as to protract rod 32 forabutment against valve stem 3 to close the balanced valve 22 and thereby shut off the feed water supply until the water level in the boiler is again lowered. The normal water level is thus antomatically maintained, and by axially adjusting rod 32 the opening and closing of valve 22 may be regulated with a degree of accuracy insuring the maintenance of any predetermined water level.

In practice the steam pipe 24 pr terably slopes downwardly throughout its length so that condensation will drain into the control device and thus maintain circulation of the steam and water for insuring practically instantaneous operation or" the automatic control; and if desired the control device may be inclined slightly from the horizontal so as to slope downwardly toward the end having ports 3536, thereby insuring replacement of all of the steam or water in tubeBl when the water level varies, and consequently providing a marked change in temperature in the expansible tube so as to positively retract and project the rod 32. While draining the condensate into the control device may have some tendency to make for less sensitivity due to reduction in the temperature differential between the steam and water, I have found in practice that such reduction in the temperature differential is very slight, due to the ports'3536 being diametrically opposite one another and the control device slanting downwardly toward said ports so that the condensate drains though pipes 24-25 without appreciably backing-up in. the control device and consequently without appreciably affecting the temperature difierential which expands and contracts the tube 31, and I have also found that any loss of efficiency resulting from such reduction in the temperature differential, is more than compensated for by the marked increase in etiici'ency and sensitiveness which is obtained by draining the condensate so as to maintain circulation through the control device via pipes 24-25.

The detachable coupling 87 permitsthe entire control device tobe removed after clos ing valves 11 without disturbing the valve casing 20, and the abutting engagement at heads l3d6 without axial connections, permits retraction of valve stem 24 without it positively unseating valve 22 and also provides for withdrawal of rod 32 while leaving its remaining elemen s in assembled reut1on. By setting the jam nut for any desired clea ed by flushing it with steam when such action is desirable, by closing the water pipe 25 ,as tor'example by means oi a valve 70, an'd'ope'mng the stop-cock 58 so that steam siippliecl'tlii'ough pipe 24: will freely circulate through the tube 31.

The invention thus provides an extremely practical device adapted for accurate adjustment to automatically control the feed watersupply to a boiler.

It will also be noted that the provision of means tor readily backing oil red 32 and then returning it to its nicely adjusted position by the abutment 0t jam nut 62 against the bearing 51, permits a positive flushing action at the main controlled valve 22, since by thus backing oi the rod 32 the valve 22 is permitted to fully open and the feed water supply will thus thoroughly flush the valve seat2l of any accumulation oi sediment It is fragmentary packing and the like. thus possible to back oil rod 32 and provide for such flushing action whenever the action of the device indicates that such cleaning of the control valve is desirable, and the proadjustment, therod 32 may bereadily un; screwed when 1t s necessaryto disassemble "ioo ios

fixed at one end relative to the conduit and.

surrounding the valve stem, a tube projecting substantially horizontally from the opposite end of the sleeve, a connection between the container and sleeve for maintaining the same liquid level in the container, sleeve and tube; said tube being adapted for expansion andcontraction in accordance with the liquid level therein, a rod extending through the tube and sleeve, with one end of the rod fixed relative to that end of the tube which is refor controlling opening andclosing of the valve in accordance with axial shitting of the rod.

2. In a feed water control for a boiler, a valvular control in the feed water line, conduits leading from the boiler above and below the normal water level, and a thermostatic means connected at one end to both of said conduits for reception of water or steam in accordance with the water level in the boiler for contracting or expanding said thermostatic means, said contraction and expansion controlling the closing and opening of the valvular control, and said conduits being disposed for drainage of condensate so as to maintain circulation through said aforementioned end of the thermostatic means via said conduits, and the thermostatic means slanting downwardly toward its aforementioned end for said drainage of the condensate through the conduits without it backing-up in the thermostatic means.

3. In a feed water control for a boiler, a valvular control in the feed water line, conduits leading from the boiler above and below the normal water level, and thermostatic means connected to said conduits for reception of water or steam in accordance with the Water level in the boiler for contracting or expanding said thermostatic means, said contraction and expansion controlling the closing and opening of the valvular control, and the said conduits being disposed for drainage of condensate and communicating with the thermostatic means in vertical alinementso as to drain said condensate through the thermo static means without the condensate backingup in the thGlmOStHtlC means, the said drainage of condensate maintaining circulation through the thermostatic means via the conduits.

4. In combination, a container for liquid, a conduit for delivering liquid to the container, a valve in the conduit, a substantially horizontal rod adapted for axial shifting to actuate the valve, a tube fixed at one end relative to the conduit and surrounding the rod, and a connection between the container and tube for maintaining the same liquid level in the container and tube, the tube being adapted for expansion and contraction in accordance with the liquid level therein, and the rod being fixed relative to that end of the tube which is remote from the conduit so that the rod is axially shifted in accordance with expansion and contraction of the tube.

In testimony whereof he has aflixed his signature to this specification.

BENJAMIN F. DOVVD. 

